A concise approach for central core of trigolutes: Total synthesis of trigolute B and 3-epi-trigolute B and analogues

A concise approach comprising a combination of the Pd- or Ir-catalyzed Tsuji-Trost allylation and olefin dihydroxylation/acid catalyzed lactonization has been developed to construct the central spirolactone core of trigolutes with the requisite functional groups. A large number of analogues of trigolute B have been synthesized. Furthermore, the synthesis of both (+/-)-trigolute B and (+/-)-3-epi-trigolute B has been accomplished in 4-5 steps from easily accessible building blocks. (C) 2016 Elsevier Ltd. All rights reserved.